東華大學圖書館 |

Language: English

Help

回圖書館首頁

手機版館藏查詢

Back

Switch To: Labeled | MARC Mode | ISBD

Modeling heat and mass transfer duri...

University of California, Davis.

Linked to FindBook

Google Book

Amazon

博客來

Modeling heat and mass transfer during air impingement thawing of frozen foods.

Record Type:	Language materials, printed : Monograph/item
Title/Author:	Modeling heat and mass transfer during air impingement thawing of frozen foods./
Author:	Anderson, Brent Andrew.
Description:	225 p.
Notes:	Adviser: R. Paul Singh.
Contained By:	Dissertation Abstracts International65-09B.
Subject:	Agriculture, Food Science and Technology. -
Online resource:	http://pqdd.sinica.edu.tw/twdaoeng/servlet/advanced?query=3148424
ISBN:	9780496073498

Modeling heat and mass transfer during air impingement thawing of frozen foods.
Anderson, Brent Andrew.

Modeling heat and mass transfer during air impingement thawing of frozen foods. - 225 p.

Adviser: R. Paul Singh.

Thesis (Ph.D.)--University of California, Davis, 2004.

Current methods used for thawing of frozen foods are typically undesirably slow or are expensive and cause uneven thawing. One possible method for improved, rapid thawing that has not been investigated is the use of air impingement technology. The goal of this research is to develop a better understanding of the thawing process when frozen food is impinged with jets of air. To accomplish this goal, a mathematical model was developed, based on fundamental principles, that predicts the heat and moisture transport during impingement thawing; effective moisture diffusivities and heat transfer coefficients were determined experimentally for use in the mathematical model; the model was validated using laboratory experiments; and the influence of properties and process conditions on the rate of thawing was studied using a sensitivity analysis.

ISBN: 9780496073498Subjects--Topical Terms:

1017813
Agriculture, Food Science and Technology.

Modeling heat and mass transfer during air impingement thawing of frozen foods.
LDR:03278nam 2200289 a 45 001 858117
005 20100712
008 100712s2004 ||||||||||||||||| ||eng d
020 $a 9780496073498
035 $a (UMI)AAI3148424
035 $a AAI3148424
040 $a UMI $c UMI
100 1 $a Anderson, Brent Andrew. $3 1025146
245 1 0 $a Modeling heat and mass transfer during air impingement thawing of frozen foods.
300 $a 225 p.
500 $a Adviser: R. Paul Singh.
500 $a Source: Dissertation Abstracts International, Volume: 65-09, Section: B, page: 4690.
502 $a Thesis (Ph.D.)--University of California, Davis, 2004.
520 $a Current methods used for thawing of frozen foods are typically undesirably slow or are expensive and cause uneven thawing. One possible method for improved, rapid thawing that has not been investigated is the use of air impingement technology. The goal of this research is to develop a better understanding of the thawing process when frozen food is impinged with jets of air. To accomplish this goal, a mathematical model was developed, based on fundamental principles, that predicts the heat and moisture transport during impingement thawing; effective moisture diffusivities and heat transfer coefficients were determined experimentally for use in the mathematical model; the model was validated using laboratory experiments; and the influence of properties and process conditions on the rate of thawing was studied using a sensitivity analysis.
520 $a Moisture diffusivities for Tylose were determined using a drying method and a concentration-distance method. The variation of diffusivity with temperature was fit well using an Arrhenius relationship. Effective heat transfer coefficients for impingement thawing of frozen foods were determined using an inverse method and found to vary both with position and with changes in surface temperature. Heat transfer coefficients were significantly lower at temperatures below 0°C than at higher temperatures due to the frost formation. Temperatures matched well between predictions and experiments. Differences between the two can be partly attributed to different effective heat transfer coefficients resulting from variable humidity during the experiments and possible differences in frost formation. Virtually all mass transfer occurred in the top few millimeters of the samples. The model gave good results for some cases, but tended to under predict moisture contents of the samples because the added moisture due to frost and condensation was not included in the model. Impingement jets reduce thawing times by over 75% for both the Tylose samples and the individually wrapped bratwurst packages. The sensitivity analysis found that product thickness, air temperature, and heat transfer coefficient have the greatest impact on thawing times. Using an average heat transfer coefficient rather than one that varies with position or surface temperature can cause substantial variation in the temperature versus time curves.
590 $a School code: 0029.
650 4 $a Agriculture, Food Science and Technology. $3 1017813
650 4 $a Engineering, Agricultural. $3 1019504
690 $a 0359
690 $a 0539
710 2 $a University of California, Davis. $3 1018682
773 0 $t Dissertation Abstracts International $g 65-09B.
790 $a 0029
790 1 0 $a Singh, R. Paul, $e advisor
791 $a Ph.D.
792 $a 2004
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoeng/servlet/advanced?query=3148424